key: cord-0712593-bglc9bzn
authors: Cárdenas, Carmen Hernández; Lugo, Gustavo; García, Diana Hernández; Pérez-Padilla, Rogelio
title: Comparación de las características clínicas y mortalidad debidas a Síndrome de Distrés Respiratorio Agudo debido a COVID-19 versus Influenza A-H!N!pdm09
date: 2021-06-05
journal: Med Intensiva
DOI: 10.1016/j.medin.2021.05.014
sha: f4a40719faf9d38d366be8cfd23f189e643f7e2e
doc_id: 712593
cord_uid: bglc9bzn

nan

Author contributions: authors 1 and 4 concept; authors 2 and 3 data collection; authors 2 and 4 statistical analysis; autors1,2 and 4 elaboration of the manuscript.

April 2009 (1), causing acute hypoxemic respiratory failure (AHRF), acute respiratory distress syndrome (ARDS), with an associated mortality ranging from 25.1%-41% at different sites (2) . The World Health Organization estimates that influenza affect 5-10% of adults and up to 20-30% of children, especially in immunosuppressed, at extremes of life, and in persons with comorbidities (3) and approximately 390,000 deaths annually.

The outbreak of respiratory infection by the novel SARS-CoV-2 started in December 2019, in Wuhan (Hubei Province), China (4) . From this city, the outbreak has been spreading to most countries worldwide in a severe pandemic (5) . Up to December 3, 2020, the COVID-19 pandemic has given rise to a total of 62 million cases and 1.4 million deaths around the world (5), mainly due to respiratory failure, although a long list of complications in various organs and Page 3 of 10 J o u r n a l P r e -p r o o f 3 systems have been described. The COVID-19 disease is associated with severe pneumonia, AHRF, and ARDS, requiring intensive care and ventilatory assistance in up to 5% of cases, and with a reported mortality ranging from 30-60% (average 41%) at different sites (6) . including PaO2/FIO2, platelets, bilirubin, creatinine, mean arterial pressure, and use of vasopressors. Glasgow score was the same as all the patients were sedated.

The information obtained was stored in an electronic database and the main outcome was survival from the ICU. Time to death was evaluated by a Cox proportional risk model, comparing the group with COVID-19 and that of the patients with influenza in non-adjusted models, and adjusting for age, gender, obesity, comorbidities, and biomarkers, and mechanical ventilation parameters.

Statistical analysis was performed with SPSS (version 21) and with STATA (version13.0) statistical software packages. Two-sided p values of <0.05 were considered statistically significant. Table 1 presents the main characteristics of patients with influenza (n = 94) and with COVID-19 (n =147). Patients with influenza had a slightly higher body mass index (BMI), lactic dehydrogenase glucose, and SOFA score, and a higher proportion of individuals with obesity, fever, shortness of breath, muscle pain, and headache, with lower neutrophils. Patients with influenza arrived for care in a worse situation (Table 1) , they were more hypotense, hypoxemic, requiring vasopressors more frequently, with a higher SOFA score. Those with COVID-19 had a higher crude ICU mortality (39% vs. 22%; Fisher exact test; p = 0.007; log- Patients with COVID-19 had a substantially higher lethality than those with influenza, despite both being in respiratory failure, both with ARDS, and after considering various predictors of death such as age, sex, some laboratory measurements, and ventilatory parameters, indicating in COVID-19 more severe lung damage and fewer possibilities of recovery.

Influenza and COVID-19 may cause severe damage to the lungs, to other organs, and may cause death, and it is unknown whether this may be attributed to direct viral injury, to an exaggerated inflammatory reaction, or to the often mentioned cytokine storm (8) in addition to personal susceptibility. Patients with Page 6 of 10 J o u r n a l P r e -p r o o f 6 COVID-19 have been compared with those with influenza and lacked a difference in cytokine levels (8) . The findings of CT scanning overlap in the two infections (9), but patients with COVID-19 manifested vascular inflammation, and immunothrombosis (10) to a higher degree than those with influenza. In addition, all of our patients received Oseltamivir, and an influenza vaccine of variable affectivity is available, although only a small proportion of our patients were vaccinated (5% of those arriving at the ICU). Most of our patients with COVID-19 received systemic corticosteroids, but an antiviral treatment and a vaccine were not yet available.

Our study shows limitations such as a small cohort of patients and coming from a single high specialty center. However, it is prospective, and both cohorts were studied with few weeks of difference.

In conclusion, patients with respiratory failure and ARDS from COVID-19 treated in an ICU entertain a substantially increased risk of death compared with similar patients with Influenza A-H1N1, even adjusting for SOFA score and other relevant risk factors for mortality. 25 Comorbidities were similar in both groups, except for chronic renal failure. All patients had lung opacities in a CT scanning of the thorax. VR, ventilatory ratio. SOFA is the sequential organ failure assessment score (see text). 

Pneumonia and respiratory failure from swine-origin influenza a (H1N1) in Mexico

Global variability in reported mortality for critical illness during the 2009-10 influenza a(H1N1) pandemic: A systematic review and meta-regression to guide reporting of outcomes during disease outbreaks

Influenza (seasonal)

Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: A descriptive study

World Health Organization. Coronavirus disease (COVID-19) situation report

Outcomes from intensive care in patients with COVID19: A systematic review and meta-analysis of observational studies

Physiologic analysis and clinical performance of the ventilatory ratio in acute respiratory distress syndrome

Distinct inflammatory profiles distinguish COVID-19 from influenza with limited contributions from cytokine storm

Chest computed tomography findings in COVID-19 and influenza: A narrative review

Vascular neutrophilic inflammation and immunothrombosis distinguish severe COVID-19 from influenza pneumonia

BMI, body mass index

SOFA is the sequential organ failure assessment score (see text). For the crude model (only COVID-19). Log likelihood -371